Developing a pipework scanner system using EDXRD

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Developing a pipework scanner
system using EDXRD
Jamieson Lock
Natural Science (Physics and Chemistry)
Undergraduate
College of Management and Technology
Overview
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X-ray diffraction and its application
Defects in pipework
Previous work on project
Project aims
Initial work done towards project
Problems and steps taken to overcome
them
• Where the project is going next
College of Management and Technology
X-ray diffraction
nλ = 2d sin(θ/2)
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Applications
• Inter-planar spacing of a microstructure
– Phase transformations
– Stresses – with high intensity X-rays
• Amorphous structure still gives result
– Security – explosives in luggage
– Health – cancerous tissue
• Locating possible defects in pipework
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Phases of steel
• Ferrite
– Body centred cubic
• Austenite
– Face centred cubic
• Martensite
– Body centred tetragonal
• Chromium carbides
– Simple orthorhombic
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Previous work
• Research into
ADXRD and EDXRD
• EDXRD chosen –
calculation heavy, but
uses single detector
and does not require
monochromatic X-ray
source
• Tungsten collimator
• Brittle fracture
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Source: Development of a prototype pipework scanning system using Energy Dispersive X-ray Diffraction
- Bradley, Garrity, Jenneson, Vincent
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Previous error
• Vertical ribbon beams
• Large angular error possible
• Systematic error – calculated to be 11.5º rather
than 6.25º
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Initial state of project
• New collimator
• Had not been tested
– Crack visible
• Clamp system required
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Initial work
• Clamp designs
• EDM
– Electrical discharge
machining
• Clamp fabrication
• Operator training
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Set up
• Holder and framework
set up
• Better than expected
– Easily adjustable
– No clips
• Errors in previous
work analysed
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Initial spectra
3000
2500
Count
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1000
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800
1000
Detector Channel
Counts (over 5 minutes)
250
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100
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• Spectra taken before
calibration
• Heavy noise
• Detector found to be
broken
• CdTe → CZT
• Tungsten K lines
• Still no diffraction
peaks
100
Energy (KeV)
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Future work
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Alignment problem
Solve other problems
Possible new collimator design
Gain spectra for known samples
Weld decay
Martensitic structure
Other phases/microstructures
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Summary
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X-ray diffraction and uses
Defects and associated phases
Previous work – proof of concept
Project details
Work so far
Current situation
Future aims
College of Management and Technology
Dr David Garrity – Supervisor
Dr Paul Chard-Tuckey – Group Manager
Clare Scudder – Head
of Nuclear
Thank
youDept.
Dr Ian Giles – DE&S UDS Project Manager
Anyplacement
questions?
Lewis Kiely – Fellow
Student
Samantha Morris – Placement Co-ordinator
Dr Steve Andrews – Placement Tutor
Paola Hayes – Health Physicist
Terry McCarthy – Lab Assistant
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Extra slides
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Apparatus
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Varian 225 kV source
Gulmay 3.2 kW supply
Gulmay MP1 controller
AmpTek XR-100T CdTe Detector
– PX4 digital pulse processor
• AmpTek XR-100T CdZnTe Detector
– Pocket MCA
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First design
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Alignment problem: solutions
A. Check horizontal
alignment
Still no peaks & Collimator broke
B. Use old collimator
with new holder
Barely fits & Minimal flux
C. Try original
aluminium collimator
To be arranged
College of Management and Technology
Spectra
250
Counts (over 5 minutes)
200
150
100
50
0
0
10
20
30
40
50
60
70
Energy (KeV)
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80
90
100
Desired peaks (austenite)
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D111 – 2.06 Å – 38.36 keV
D200 – 1.78 Å – 44.39 keV
D220 – 1.26 Å – 62.71 keV
D113 – 1.07 Å – 73.90 keV
D222 – 1.03 Å – 76.72 keV
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X-ray linearity test
X-ray tube linearity test
400.00
350.00
Dose (mGy/min)
300.00
250.00
200.00
150.00
100.00
50.00
0.00
0.0
5.0
10.0
15.0
20.0
Tube current (mA)
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25.0
100kV
30.0
150kV
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